1909.] Humble Bee and Pollination of Red Clover. 753 



spores of the fungus in the soil is known, but the sterilisation 

 of the soil as described in Leaflet No. 75 is recommended. 



Phoma grossularice, Schulz., was present on gooseberry 

 specimens from Faversham ; and violet root rot (Rhizoctonia 

 violacea), described in Leaflet No. 171, was found to be attack- 

 ing a potato crop of which specimens were received from 

 Cheadle. 



Time of Spraying, — In connection with the use of sulphate 

 of copper and caustic washes for spraying purposes, a corre- 

 spondent asks if January is the best month to use sulphate of 

 copper to be followed by a caustic wash in February. Solu- 

 tions of sulphate of copper and of caustic soda kill, or at all 

 events injure, leaf-buds that are commencing to swell, so 

 that the character of the weather is of more importance than 

 the actual time of the year as an indication of danger in 

 applying these sprays. The leaf-buds of certain bushes will 

 begin to move during a mild February, and under such con- 

 ditions it would then be too late to spray, whereas in the 

 event of hard weather there would be no danger. 



The life history of the Humble Bees (genus Bombus) differs 

 from that of the Hive or Honey Bee {Apis mellifica). When 

 the weather becomes colder at the end 

 The Humble Bee °f tne year all the inmates of the nest 

 and the Pollination of a Humble Bee die except the large 

 of Red Clover. queens, as, unlike the hive of a Honey 

 Bee, where typically a single queen 

 only is tolerated, the nest of a Humble Bee may contain a 

 number of queens. All the males or drones die, all the 

 workers die, and small queens die, while the large queens 

 seek some cosy place in which to pass the winter. In the next 

 spring these queens issue from their hibernating places, and, 

 each choosing a suitable place for a nest, acts as the foundress 

 of a new colony. As soon as a suitable hole is found, the 

 queen makes a nest, in which several eggs are laid. From 

 these first-laid eggs workers in due course develop, and 

 undertake the duties of the nest other than the maternal duties 

 to which — now that workers are present — the queen limits 



